My pay week goes from Sun - Sat but whenever I do payroll it automatically defaults to show a pay date of Friday (before the Sat end of week date). How to change to Sun?

I've got the steps you need to change the default pay date to Sunday, tonyamarsh41-yah.

Updating your default pay date to Sunday is pretty easy. It can be done in just a few clicks. Let me show you how:

1. Navigate the Payroll tab and select Employees.
2. Select the name of the employee.
3. From Employment details, select Edit.
4.  Select the pay schedule for the employee from the Pay schedule dropdown.
5. Enter the required fields.
6. Click Save.
   
   

I've added a screenshot for your visual reference:

You can use this article for more details: Set up and manage payroll schedules.

I've also added this link to take a look at your business finances. These provide several payroll reports you can view about your business and employees: Run payroll reports in QuickBooks Online Payroll.

You can always post again if you have other questions in mind. I'm here to help.